It is becoming better understood that radiation resistance in glioblastomas (GBMs) may be secondary to a self-renewing subpopulation of cells in the bulk tumor that form neurospheres in culture. This population has been referred to as Glioma stem cells (GSCs). One of the limitations regarding the use of GSCs is that these studies require fresh tumor biopsy samples obtained from patients, and can be extremely difficult to culture, propagate, and perform treatment-response assays. This report describes the generation of a self-renewing population of GSCs derived from commercially available U87 cells using NOD-SCID mice as carrier. The tumors were dissociated to obtain GSCs that demonstrate stem-like properties and high degree of chemo and radiation resistance. Pathological analysis of tumors obtained using GSCs exhibit all the histological hallmarks of human GBMs which is quite uncommon in GBM rodent models and hence could serve as a better model for pre-clinical study. We have shown that MGH87GSCs have an enhanced tumorogenicity than parental U87 and about 500 cells are sufficient to form tumors. To understand the transcriptome and accompanied proteome better, we explored the gene expression profiles of MGH87GSC and U87. We have shown that these GSCs are plastic like stem cells and can be directed towards a particular progeny within neural lineage by providing suitable growth factor. Our objective was to understand the genetic and biochemical mechanisms that control the self-renewal phenotype, asymmetric subdivision, chemo and radiation resistance and the role of the GSC niche in regulating the biological properties of GSC. Through this model we anticipate to devise therapeutic strategies to target this sub population of GSCs within GBMs to eradicate treatment resistance and tumor recurrence.
Cells isolated from residual intracranial tumors after treatment express iPSC genes and possess neural lineage differentiation plasticity.
Specimen part, Cell line
View SamplesOrganophosphorus compounds may induce neurotoxicity through mechanisms other than the cholinergic pathway, which need to be unraveled by a comprehensive and systematic approach such as genome-wide gene expression analysis.
Toxicogenomic studies of human neural cells following exposure to organophosphorus chemical warfare nerve agent VX.
Specimen part
View SamplesTranscriptome analysis by RNAseq of leukemia model promoted by MLL-Af4 or MLL-AF9 fusion proteins. We find each fusion protein promotes a specific gene signature correlating to those identified in patients Overall design: Human CD34+ hematopoietic stem and progenitor cells were transduced with retrovirus expressing MLL-Af4 or MLL-AF9. Transduced cells were transplanted into immunodeficient mice to induce lymphoid leukemia or placed in myeloid in vitro culture. CD19+ lymphoid leukemia cells (3 AF9, 6 Af4), control health CD19+CD34+ proB cells (n=3) and 4 pairs of Af4 and AF9 CD33+CD19- myeloid culture cells were collected for RNA-seq
Instructive Role of MLL-Fusion Proteins Revealed by a Model of t(4;11) Pro-B Acute Lymphoblastic Leukemia.
No sample metadata fields
View SamplesLung cancer is the leading cause of cancer related mortality worldwide, with non-small cell lung cancer (NSCLC) as the most prevalent form. Despite advances in treatment options including minimally invasive surgery, CT-guided radiation, novel chemotherapeutic regimens, and targeted therapeutics, prognosis remains dismal. Therefore, further molecular analysis of NSCLC is necessary to identify novel molecular targets that impact prognosis and the design of new-targeted therapies. In recent years, tumor “activated/reprogrammed” stromal cells that promote carcinogenesis have emerged as potential therapeutic targets. However, the contribution of stromal cells to NSCLC is poorly understood. Here, we show increased numbers of bone marrow (BM)-derived hematopoietic cells in the tumor parenchyma of NSCLC patients compared with matched adjacent non-neoplastic lung tissue. By sorting specific cellular fractions from lung cancer patients, we compared the transcriptomes of intratumoral myeloid compartments within the tumor bed with their counterparts within adjacent non-neoplastic tissue from NSCLC patients. The RNA sequencing of specific myeloid compartments (immature monocytic myeloid cells and polymorphonuclear neutrophils) identified differentially regulated genes and mRNA isoforms, which were inconspicuous in whole tumor analysis. Genes encoding secreted factors, including osteopontin (OPN), chemokine (C-C motif) ligand 7 (CCL7) and thrombospondin 1 (TSP1) were identified, which enhanced tumorigenic properties of lung cancer cells indicative of their potential as targets for therapy. This study demonstrates that analysis of homogeneous stromal populations isolated directly from fresh clinical specimens can detect important stromal genes of therapeutic value. Overall design: We sorted pure populations of the immature monocytic myeloid cells (IMMCs), neutrophils (Neu), and epithelial cells (Epi) from tumors and adjacent lung tissues of stage I-III lung adenocarcinoma patients. RNA samples (totally 17 samples) were sequenced: from tumor IMMC (n=3), Neu (n=2), Epi (n=2); from adjacent lung IMMC (n=3), Neu (n=4), Epi (n=3).
Identification of Reprogrammed Myeloid Cell Transcriptomes in NSCLC.
No sample metadata fields
View SamplesIschemic cardiopathy is the leading cause of death in the world, for which efficient regenerative therapy is not currently available. In mammals, after a myocardial infarction episode, the damaged myocardium is replaced by scar tissue featuring collagen deposition and tissue remodelling with negligible cardiomyocyte proliferation. Zebrafish, in contrast, display an extensive regenerative capacity as they are able to restore completely lost cardiac tissue after partial ventricular amputation. Due to the lack of genetic lineage tracing evidence, it is not yet clear if new cardiomyocytes arise from existing contractile cells or from an uncharacterised set of progenitors cells. Nonetheless, several genes and molecules have been shown to participate in this process, some of them being cardiomyocyte mitogens in vitro. Though questions as what are the early signals that drive the regenerative response and what is the relative role of each cardiac cell in this process still need to be answered, the zebrafish is emerging as a very valuable tool to understand heart regeneration and devise strategies that may be of potential value to treat human cardiac disease. Here, we performed a genome-wide transcriptome profile analysis focusing on the early time points of zebrafish heart regeneration and compared our results with those of previously published data. Our analyses confirmed the differential expression of several transcripts, and identified additional genes the expression of which is differentially regulated during zebrafish heart regeneration. We validated the microarray data by conventional and/or quantitative RT-PCR. For a subset of these genes, their expression pattern was analyzed by in situ hybridization and shown to be upregulated in the regenerating area of the heart. The specific role of these new transcripts during zebrafish heart regeneration was further investigated ex vivo using primary cultures of zebrafish cardiomyocytes and/or epicardial cells. Our results offer new insights into the biology of heart regeneration in the zebrafish and, together with future experiments in mammals, may be of potential interest for clinical applications.
Transcriptomics approach to investigate zebrafish heart regeneration.
Specimen part, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Placing the HIRA histone chaperone complex in the chromatin landscape.
Specimen part
View SamplesThe HIRA chaperone complex, comprised of HIRA, UBN1 and CABIN1, collaborates with histone-binding protein ASF1a to incorporate histone variant H3.3 into chromatin in a DNA replication-independent manner. To better understand its function and mechanism, we integrated HIRA, UBN1, ASF1a and histone H3.3 ChIP-seq and gene expression analyses. Most HIRA-binding sites co-localize with UBN1, ASF1a and H3.3 at active promoters and active and weak/poised enhancers. At promoters, binding of HIRA/UBN1/ASF1a correlates with the level of gene expression. HIRA is required for deposition of histone H3.3 at its binding sites. There are marked differences in nucleosome and co-regulator composition at different classes of HIRA-bound regulatory site. Underscoring this, we report novel physical interactions between the HIRA complex and transcription factors, a chromatin insulator and an ATP-dependent chromatin-remodelling complex. Our results map the distribution of the HIRA chaperone across the chromatin landscape and point to different interacting partners at functionally distinct regulatory sites.
Placing the HIRA histone chaperone complex in the chromatin landscape.
Specimen part
View SamplesInhibition of miR-33 results in increased cholesterol efflux and HDL-cholesterol levels in mice. In this study we examined the effect of miR-33 inhibition in a mouse model of atherosclerosis and observed significant reduction in atherosclerotic plaque size. At the end of the study, gene expression in macrophages from the atherosclerotic plaques was assessed.
Antagonism of miR-33 in mice promotes reverse cholesterol transport and regression of atherosclerosis.
Sex, Specimen part
View SamplesThe process of neural tube closure is a highly complex morphogenetic event that results in the generation of the primordial central nervous system. During formation of the neural tube, the non-neural ectoderm separates from the neighboring neural ectoderm and forms a single layer epithelial sheet that overlies the closed neural tube. Previous work has shown that the non-neural ectoderm is necessary for proper cranial neural tube closure, however little is known about this cell population at the molecular level or how the non-neural ectoderm contributes to neural tube closure. In this study, we used a mouse genetic system to fluorescently label the non-neural ectoderm cells and FACS sorted these cells away from the other cell populations in the neural tube. We performed high throughput RNA-sequencing to identify the transcriptome of the non-neural ectoderm and compared the gene expression profile of non-neural ectoderm cells to the remaining population of cells within the neural tube in order to identify which genes are enriched within the non-neural ectoderm. This analysis provides a clue as to which underlying molecular processes may be important for non-neural ectoderm function during neural tube closure. Overall design: mTomato/mGFP dual fluorescent reporter mice were mated to Grhl3-cre mice to generate embryos that expressed a membrane-bound RFP throughout the embryo with specific expression of membrane-bound GFP in the Grhl3+ non-neural ectoderm. Embryos were dissected at 9.5 days post-fertilization and scored for correct genetic recombination. Non-neural tube tissue was dissected away and single cell suspensions were made followed by FACS to sort the GFP+ and RFP+ populations. RNA was isolated immediately and pooled samples of 1ug total RNA were used to generate libraries for sequencing with the Illumina TruSeq RNA sample preparation kit. Pooled RNA was generated from 25 individual embryos all aged betweed 21 and 25 somites. RNA-sequencing was performed on an Illumina HiSeq 2000.
Grainyhead-like 2 downstream targets act to suppress epithelial-to-mesenchymal transition during neural tube closure.
No sample metadata fields
View SamplesMonocytes and macrophages constitute important components of immune system. Monocytes differentiate into macrophages following stimulation with cytokines and/or microbial molecule. Macrophages play central role in the maintenance of tissue homeostasis, development and its restoration after injury, as well as the initiation and resolution of innate and adaptive immunity. Though macrophages were long considered to be derived from differentiation of bone marrow monocytes, recent studies have proved that tissue resident macrophages are derived from yolk sac macrophages, fetal liver macrophages, can self-replicate from local proliferation. However, during homeostatic adaptations, injury and inflammation macrophages of different phenotypes can be recruited from the monocyte reservoirs of blood, spleen and bone marrow. Our studies show that Lysophosphatidic acid (LPA), a small lipid molecule converts monocytes into macrophages. We report the gene expression profile of primary mouse bone marrow monocytes treated for 5 days with LPA with respect to control monocytes. Overall design: We have performed RNA-seq in mouse bone marrow monocytes and LPA derived macrophages from bone marrow monocytes.
Lysophosphatidic acid converts monocytes into macrophages in both mice and humans.
Age, Cell line, Subject
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